Sterility slide rule



Aug. 29, 1950 A. GREEN STERILITY SLIDE RULE Filed Nov. 1o, 1949 CYCLELESLIDE E v o M E n a E v E N CALENDAQ CYCLE SLDE Patented Aug. 29 1950UNITED STATES PATENT OFFICE STERILITr SLIDE RULE Abraham Green, NewYork, N. Y.

Application November 100, 1949, Serial No. 126,469 3 claims.. (lol.23S-89) This invention relates to a sterility slide rule.

It is an object of the present invention to provide a, sterility sliderule by means of which and upon the simple manipulation of parts, theperiods of greatest fertility in women can be determined in an accuratemanner and which requires no calculation or mental compilation to`determine the exact dates for one womans cycle in which she is fertileand in which she is sterile.

It is another object of the present invention Vto provide, on the sameslide rule, means whereby the length of the cycle can be readilydetermined by a simple manipulation of the operable parts in a reversemanner from that which they are used in determining the fertilityperiod.

Other objects of the present invention are to provide a fertility sliderule which is of simple construction, operated by a simple manipulationof the parts, adapted to receive a leap year slide, inexpensive tomanufacture, has a minimum number of parts, compact and consumes littlespace and efficient in operation.

For other objects and for a better understanding of the invention,reference may be had to the following detailed description taken inconnection with the accompanying drawing, in which:

Fig. 1 is a plan view of the slide rule embodying the features of thepresent invention.

Fig. 2 is a fragmentary plan View showing the reverse side of the rule.

Fig. 3 is a transverse sectional view taken on line 3-3 of Fig. 1.

Fig. 4 is a longitudinal sectional view taken on line 4-4 of Fig. 2.

Fig. 5 is a perspective View of the slide.

Fig. 6 is a perspective view of the holder.

Fig. 7 is a perspective view of the calendar slide bearing the days ofthe month on the reverse sides thereof.

It has been determined that the sperm cannot penetrate the cervicalmucus for on the average of ten to fourteen days after the menstrualperiod. Thereafter, there is a fertile period which lasts for abouteight days. During the remainder of the cycle, the cervical mucus is notpenetrable by the sperm except during menstruation. With these facts inmind and by a simple manipulation of the slide rule about to bedescribed in detail, the woman, upon knowing the exact length of hermenstrual cycle, can set the parts of the slide rule so that the exactdates when fertility starts and ends can be quickly and accuratelydetermined.

Referring now to the figures, Hl represents a long flattened sleeve inthe opposite sides of These windows lie intermediately the length Of thesleeve. Intermediate the length of the opening are darkened indicatingareas l5 by the use of which the dates of fertility and the period inwhich conception can occur are readily determined. Outside of thesedarkened areas are clear areas which give the sterility periods and thedates of the beginning and ends of these periods. Also on the sleevesare a series of consecutive numbers, as indicated at IB, which gives thevarious cycle days to which outer slide sleeve il can be adjusted. Thesleeve il has a small window i8 through which the number of days can bedetermined. The slide sleeve I1 will be adjusted to a given number ofdays, as for example twenty-nine, as viewed in Figs. l and 2. This slidesleeve is notched at its lower end, as indicated at I9 and 28 at oneside of the sleeve and at 22 and 23 at the opposite side of the sleeve.

Slidable through the sleeve lil is a calendar slide 24. This calendarslide is divided into four columns-A, B, C, and D. The column A is usedwhen the first day of flow of each menstrual period occurs betweenJanuary 1 and March 3l. The column B is used when the rst day occursbetween April 1 and June 30. The column C is used when the first day offlow occurs between July 1 and September 30. The column D is used whenthe first day of flow occurs between October l and December 31. It willbe seen that the same calendar slide thus bears the dates for the entireyear. If the year is a leap year, a slightly different calendar slide isused. This calendar slide will include the extra day of the year.

In operation, if it be assumed that the rst day of iiow of the womanunder consideration is, as viewed in Fig. 1, o-n February 11, theprocedure Iwill be as follows. The slide I1 is rst adjusted to theparticular cycle number of the woman. For example, if the cycle isconcluded in twentynine days, the slide l1 is adjustable to the twentynine day listing as found in the numbers indicated at I6. This numbertwenty-nine will appear through the opening I8 of the slide sleeve Il.Thereafter, the calendar slide is moved so that the date of rst flowday, or February l1, is adjacent the arrow 25 and within the notch 22.By reading downwardly upon the calendar slide in the A column, it willbe found that the first day of fertility will be February 20. Thisperiod will last through until February 29 and there- 3 after the womanwill be sterile. As the arrow, as indicated at 2B, the date of firstflow for the following period can be read. The same procedure is used ifthe other columns on the calendar slide are used.

To determine the days of the cycle, the current first day of flow is setadjacent arrow 26, then the cycle slide is moved until the arrow 25 isadjacent the rst day of flow of the last menstrual period. The cycle isthe number that appears through the window I8 of the slide l1.

It should 'accordingly be apparent that the number of days of the cyclecan be readily determined from the rule and also the exact dates ofbeginning of fertility and the ending of the same. By the same means,the dates ofvsterility can be determined. As shownin Fig. 2,-thedifferent scales C and D are viewedV from the opposite side of the rule.1t is seen that it "isan easy matter for the woman to determine theseperiods and the exact dates thereof.

The slide shown in Fig. l has the lFebruaryy 29 date marked thereon andis the slide that is used on a leap year. The slide shown in Fig- '7,and indicated by the numeral 24', is theslide that is used on otheryears.

While various changes may be made in the detail construction, it shallbe understood that such changes shall be within the spirit and scope ofthe present invention as defined bythe appended claims.

What is claimed isz 1. A sterility and fertility slide rule comprising aflattened sleeve having an elongated window therein, a fertilityindicating area being disposed along the opening and the sides thereof,said sleeve having cycle clay indications thereupon, a calendar slideadjustable through thesleeve and having date markings thereupon, and aVslide sleeve adjustable upon the attened sleeve and over the opening tolocate the slide sleeve such that a reading can be made with relationthereto upon the calendar slide, said slide sleeve having an openingtherein through -which the number of cycle days can be observed.

2. A sterility and fertility slide rule comprising va flattened sleevehaving an elongated Window therein, a fertility indicating area beingdisposed along the opening and the sides thereof, said sleeve havingcycle day indications thereupon, a calendar slide adjustable through thesleeve and having date markings thereupon, and a slide sleeve adjustableupon the flattened sleeve and over the opening to locate the slidesleeve such that a reading can be made with relation thereto upon thecalendar slide, said slide sleeve having an opening therein throughwhich thefnumber of cycle days can be observed, said slide sleeve havinga notch along its lower edge, an arrow indication extending along theinner side of the notch togivefindication of the rst day of flow.

V3. A sterility and fertility slide rule comprising afiiattened sleevehaving an elongated window therein,a fertility indicating area beingdisposed along the opening vand the sides thereof, said sleevehavingcycle day indications thereupon, a calendar slide adjustable through thesleeve and having date lmarkings thereupon-and va-,slide sleeve'adjustable upon the llattenedsleeve-'and over the opening to locate theslide sleeve 4such that a reading can be madefwith relation theretoupon. the calendar slide, said slide .sleeve having an opening thereinthrough which the number .of vcycle days can be observed, said slidesleeve having a notch along its lower edge, an arrow indicationextending along the inner side .of the notch to give indication of therstday of flow, andsaid .flattened sleeve havingv an arrow indicationalong the lower end of the openingA in the vflattened sleeve wherebythe-first day of the flow ofthe next period can be determined from vthecalendar slide.Y

VABRAHAM* GREEN.

REFERENCES CITED The'iollowing references. `are of record in the .nievrof' this patent:

' UNITED STATES PA I EN TS Number Name Date 1,983,062 Anderson Dec. 4,1934 2,161,345 Gates June 6,. 1939 2,494,291 Fay Q Jan. 10, 1.950

